Calculating device.



PHILIP E. YOUNG, OF FA IRHAVEN, MASSACHUSETTS.

CALCULATING DEVICE.

To all whom it may concern Be it known that I, PHILIP E. YOUNG, acitizen of the United States, residing at Fairhaven, in the State ofMassachusetts,

5 have invented certain new and useful Improvements in CalculatingDevlces, of which the following is a specification.

My invention relates to a calculating device of the slide rule type anda general object of the invention is to provide a device for graphicallydetermining the sum of several factors, each taken in differentproportions to a definite numeral and specifically one object of theinvention is to provide a means for quickly determining the specificdensity of a compound from the known percentage of its ingredients andtheir known specific densities.

Another object of the invention is to provide for a direct reading ofthe final resulting sum or, in the i tain a direct reading of theresulting specific density of the compound.

Various other objects and advantages of the invention will be in partobvious from an inspection of the accompanying drawings and in part willbe more fully set forth in the following particular description of oneform of mechanism embodying the invention, and the invention alsoconsists in certain new and novel features of construction andcombination of parts hereinafter set forth and claimed.

One illustrative means by which the above outlined objects may beattained is to provide a chart plotted with a plurality of righttriangles superposed on each other and having a common side hereinafter,for convenience of reference, called the unit line, which line may bedivided into percentages or other fractional parts'to indicate theproportions of the ingredients in the compound. The apexes of the anglesare coincident at the zero point of the percentage scale. The trianglesare to each other as the trigometrical cotangents of the reciprocals offactors which indicate the known specific densities of the severalingredients composing the compound when the percentage scale isconsidered as unity. The line forming the sides opposite these angles,hereinafter called the base line, intersects the hundred per cent. markon the unit line and the line is graduated from the unit line by thehypotenuses of the angles at distances which Specification of LettersPatent.

device illustrated, to ob- Patented Oct. 10, 1916.

Application filed March 12, 1914. Serial No. 824,094.

are to each other as the reciprocals of these factors.

The resulting specific density is obtained v by adding the several baselines of triangles which are formed, one for each ingredient,

similar to the plotted triangle on the chart.

The base line of each of these constructed triangles intersects the unitline at that percentage mark which indicates the percentage of thisingredient in the compound. The addition of these several constructedbase lines is made directly on a scale;which is graduated as is the baseline except that the graduations are in the opposite order that istoward the unit line.

In the drawings: Figure 1 is a plan view of a device illustrating apreferred embodiment of my invention; Fig. 2 is an end view looking downupon the upper side of the device shown in Fig. 1, and Fig. 3 is atransverse sectional view taken at the portion of the line 33 of Fig. 1which is adjacent the rule and looking in the direction indicated by thearrows.

There is shown a suitable support 1 vcomprising a bottom board 2 havingoppositely disposed grooved guides 3 within which is slidably mounted aboard 4 which board preferably may be entirely removed and reinsertedwith the opposite face uppermost. One or both faces of the board maycontain charts suitably aflixed thereto and arranged to containdifferent data for the several operations of which this device iscapable.

The chart illustrated includes a scale 5 extending in the direction ofmovement of the board 4 which scale is graduated in percentage marksfrom 0 to 100 per cent. or in other suitable fractional factors. Thescale slides relative to a fixed point of reference indicated by thearrow '6 on one of the guides or on some other suitable part of thefixed support.

A series of right triangles are plotted on the chart which triangleshave a common side 7, designated as the unit line orcoordinate, which iscoincident with, or, as illustrated, is positioned opposite andcorresponds in length and direction with the percentage scale 5. Theother side of the triangles form a line 8, designated for convenience ofreference as the base line, which is nor mal to the 100 per cent. ofunity mark on the fraction scale and the hypotenuses 9 of the trianglesintercept the base line at "'9.-

as possible so as to avoid parallax.

tances from the unit line which are to each other as the reciprocals ofthose known factors which indicate the specific densities of the severalingredients of the compound.

The unit line 7 and all of the hypotenuses pass through a point 10 whichis coincident with or directly opposite the zero pointon the scale 5.The point 10 may be considered as the intersection of coiirdinates, oneof which is the unit line 7 and the other of which is normal to the zeropoint on the scale5. I

A cross slide 11 is mounted on the fixed track 12 for movementtransversely of the unit line and has a pointer 13 fixed thereto andmovable on a line with the pointof reference 6. This slidehas aplurality of scales extending longitudinally thereof for use with thedifferent charts on the different boards 1. In connection with the charthereinbefore specifically described, reference will be made to the scale14 which has a zero point 15 opposite the pointer 13 and is graduatedfrom this zero point toward the unit line in distances which are toeachother as the re ciprocals of progressing numbers and corresponds to thescale 8 eXcept that it is reverse in direction.

A rider 16, such as is usually used on slide rules, is mounted on thecross slides 11 for sliding movement along the'scale 14. This rider hasa hair line 17 disposed across the scale 14 and has a pointer 15 whichis in line with the hair line and is disposed as close to thehypotenuses ofv the triangles The support has a fixed stop 19 sodisposed that the hair lines coincide with the unit line when the rideris in contact with this stop.

For convenience in illustrating the operation of the device it will beconsidered that the diagonal or hypotenuse 20 indicates zinc oxid andpasses through the graduation mark which is positioned unit distancefrom the line 7; that the diagonal 21 indicates sulfur and passesthrough the graduation mark positioned unit distance from the line 7,and the diagonal 22 indicates rubber and passes through the markpositioned unit distance from the line 7.

In operating suppose the compound, the specific density of which isdesired gave the following analysis Per Specific cent. density. Zincoxid 45 5.8 Sulfur -20 2.0 Rubber 35 0.95

To get the first, 2'. e. the zinc oxid reading, the board 4 is moveduntil the 4 5% mark on the scale 5 coincides with point 6; the

' which imposes the hair line 17 on the unit line 7. With the rider inthis position on the scale 14, the board 4 is moved until the 20% markis opposite the point 6 and the cross slide 1] together with therider ismoved until the pointer 18 coincides with the diagonal 21 and the rideris again moved into engagement with the stop 19.

With the rider in this second position the operation is repeated, withthe point 6 at the 35% mark, the rider is finally moved into engagementwith the stop and the resulting specific density of the compound may beread directly on the scale 14 under the hair line 17. Consideredtheoretically this specific density is obtained by adding thereciprocals of all the quotients obtained by dividing the fractionalparts of the ingredients by the specific density of that ingredient.This may ample by the formula: v

Specific density:

WVhile the device has been described with reference to a chart fordetermining specific densities, it is obvious that the invention is ofbroader application and other forms of charts may be used. For instancethe base line 8 may be graduated in terms of cubic inches per pound asindicated on the scale 23 and the rule 11 may have a scale 24corresponding in direction and division to the scale 23. In case it isdesired to determine the number of cubic inches per pound in the body,the specific density is obtained by any suitable means, such as aboveoutlined, the cross slide is positioned centrally with the hair line atthe specific density and the chart is moved upward until the rider indexis at the scale 23 which will give the desired cubic inches per pound.

It is seen in general that the chart is formed of a plurality .of righttriangles, which triangles have a unitary side 7 and are to each otheras the cotangents of the reciprocals of numbers which, in the chartillustrated, indicate the specific densities of the ingredients butwhich may of course incentage of various ingredients can be foundreadily without intricate or lengthy calcu lation, consequently costscan quickly be computed. I

It is obvious that the scale may be made as large as convenient, thelarger the scale the greater the accuracy of resulting values of anycomputations of this character. Approximate values which can be obtainedrapidly are usually most desirable and this can readily be attained by asmall instrument of sufiicient size to be conveniently carriedj about inthe persons pocket.

The device may be conveniently arranged with a support such as isdisclosed and numerous slides having upon opposite sides differentcharts for the different operations incidental to the difierentcomputing operations of any particular business.

lVhile I have shown and described, and have pointed out in the annexedclaims, certain novel features of my invention, it will be understoodthat various omissions, substitutions and changes in the form anddetails of the device illustrated and in its operation may be made bythose skilled in the art without departing from the spirit of theinvention.

Having thus described my invention, I claim 1. A calculating devicecomprising a support having a guiding means, a member mounted in saidsupport for sliding movement in one direction relative thereto andhaving a chart thereon, said chart including value lines extendingdiagonally of its line of movement, a rule mounted for sliding movementtransversely of the direction of movement of the chart, and transverselyof the value lines, said rule having a scale thereon adapted tocooperate with the lines of said chart, and a rider mounted on said rulefor sliding movement longitudinally of said scale.

2. A calculating device, comprising a support having a fixed point ofreference, a member slidably mounted on said support for relativemovement thereto in one direc tion, said member having a scale withequally spaced divisions extending in the direction of movement of saidmember and across said po1nt of reference, a second scale extending atright angles to the direction of movement and intersecting said firstnamed scale at right angles thereto, said second scale having divisionsthereon spaced from a fixed point, distances which are to each other asthe reciprocals of succeeding numbers, and diagonals passing through thedivisions on said second scale and through a common point spaced fromsaid scales, a second member slidable transversely of the movement ofthe first named member and in line with said fixed point of reference,said second member having a scale thereon with divisions spaced from afixed point thereon distances which are to each other as the reciprocalsof progressing numbers, the unit distance in said second mentioned scaleand in the last mentioned scale being equal.

3. A calculating device, comprising a support, a member slidably mountedon said support for relative movement thereto in one direction, saidmember having a scale with divisions extending in the direction ofmovement of said member, a second scale extending at right angles to thedirection of movement and intersecting said first named scale at rightangles thereto, said second scale having divisions thereon spaced froma. fixed point, distances which are to each other as the reciprocals ofsucceeding numbers, and diagonals passing through the divisions on saidsecond scale and through a common point spaced from said'scales, asecond member slidable transversely of the movement of the first namedmember, said second member having a scale thereon with divisions spacedfrom a fixed point thereon distances which are to each other as thereciprocals of progressing numbers, the unit distance in said secondmentioned scale and in the last mentioned scale being equal.

This specification signedv and witnessed this 10 day of March, 1914.

ALLEN T. WEEKS, FRANCIS R. PEABODY.

